Kelluu Airship

History

The Kelluu airship is a Finnish autonomous lighter-than-air aircraft designed for persistent aerial sensing. It uses hydrogen for lift and as the energy source for its fuel-cell power system.

The 12 m unmanned aircraft combines long endurance with low-altitude data collection. Its roles include environmental mapping, infrastructure inspection, Arctic surveillance, communications support, and situational awareness.

Kelluu has developed the aircraft for civilian services and defence applications. The company operates the platforms and processes their sensor data for civilian customers, while defence organizations may acquire the hardware.

Development

Kelluu was established in 2018 to develop a small airship suitable for mass production and continuous operation. The company is based in Joensuu in eastern Finland.

In 2022, Kelluu completed a 12-hour continuous flight using hydrogen both as lifting gas and as the energy source for a fuel cell. The achievement supported the company's expansion into persistent civilian monitoring. Kelluu opened an airship factory in Joensuu in December 2022.

The aircraft subsequently participated in NATO exercises and the NATO Defence Innovation Accelerator for the North Atlantic program. Kelluu was selected as one of 15 companies from 2,600 applicants for the second phase of the program and received backing from the NATO Innovation Fund.

On 28 July 2026, Kelluu announced the establishment of Canadian operations at Area X.O, a defence innovation hub in Ottawa. The company intends to use this presence to develop persistent autonomous capabilities for Canadian Arctic conditions. Details of the expansion were published in the Kelluu announcement.

Design

Airframe and control

The Kelluu aircraft is an unmanned airship measuring 12 m in length. Hydrogen provides buoyancy, so the aircraft does not consume energy merely to remain airborne. Propellers and control surfaces provide movement, steering, and the ability to maintain position against wind.

The airship operates at low altitude and below cloud cover. Its quiet propulsion and long endurance support repeated observations over wide areas without the flight-time limitations associated with battery-powered multirotor aircraft.

Power system

Hydrogen also supplies the aircraft's fuel-cell system. Energy is consumed when the airship travels or holds position in wind. This arrangement supports missions lasting between eight and twelve hours depending on weather conditions. Kelluu has demonstrated operation in Arctic temperatures as low as −30 °C.

Sensors and data processing

The airship can carry several cameras, scanners, and other sensors simultaneously. Documented equipment includes RGB and multispectral imaging systems, thermal cameras, and sensors used for photogrammetry and acoustic monitoring.

Kelluu has reported RGB multispectral photogrammetry with resolution as fine as 1 cm per pixel. Multiple viewing angles and low operating altitude allow the system to generate detailed models of terrain, vegetation, roads, and infrastructure.

An onboard processor can analyze collected information without continuously transmitting raw data to a cloud service through 4G or 5G connections. The system is intended to combine autonomous flight, remote sensing, and artificial intelligence-based data analysis.

Navigation and communications

Kelluu developed the aircraft in an area regularly affected by satellite-navigation jamming and spoofing. NATO exercises tested its interoperability with NATO systems and its ability to produce situational-awareness data in areas where global navigation satellite system signals were jammed.

The airship has also demonstrated operation as an airborne mobile 5G base station. This capability can provide a communications node during persistent missions.

Operational history

Civilian deployments have included forest-damage detection, forest inventories, biodiversity surveys, and monitoring of saplings. The system has also been used to examine forest roads, including surface profiles, potholes, wheel ruts, and moisture conditions.

Additional applications include inspection of power lines and railways. Thermal imaging can support animal counting, while multispectral sensing can collect information for agriculture and environmental monitoring.

Defence trials during multiple NATO exercises evaluated the aircraft in Arctic and electronically contested conditions. These activities included situational-awareness missions, interoperability testing, and use as a mobile 5G base station. The available sources do not identify a military service that has formally introduced the airship into operational service.

The Canadian location at Area X.O gives Kelluu access to a network involving industry, research institutions, government organizations, and the Canadian Armed Forces. The expansion is intended to support development and adoption in Canada rather than confirm the Canadian Armed Forces as an operator.

Specifications (Kelluu unmanned airship)

General characteristics

• Type: Autonomous lighter-than-air aircraft
• Length: 12 m (39 ft)
• Lifting gas: Hydrogen
• Power source: Hydrogen fuel cell
• Propulsion and control: Propellers and aerodynamic control surfaces
• Payload: Multiple cameras, scanners, and remote-sensing instruments

Performance

• Flight endurance: 8–12 hours depending on weather; a 12-hour continuous flight was demonstrated in 2022
• Demonstrated cold-weather operation: −30 °C (−22 °F)

Mission systems

• Imaging: RGB, multispectral, and thermal imaging
• Photogrammetric resolution: As fine as 1 cm per pixel in documented survey operations
• Data processing: Onboard processing with artificial intelligence-based analysis
• Communications capability: Demonstrated mobile 5G base-station function
• Navigation environment: Tested during operations affected by GNSS jamming